Include "Open devcontainer.json" action in problems resulting from devcontainer.json

[weinand]

When using an "alpine" image in my devcontainers.json I was getting this helpful warning:

After dismissing it this not-so-helpful QuickPick showed up:

I suggest to add an action to "Open devcontainer.json" in the first alert.

[chrmarti]

Ideally we could open the folder locally and the file within it. (Need to check if the 'open folder' command supports that.)

[chrmarti]

'Open Folder Locally' now does that.